Thread-lubricating device for sewing machines



Feb. 26, 1929. 1,703,781

C. F. RUBEL THREAD LUBRICATING DEVICE FOR SEWING MACHINES Filed April 27, 1925 Patented Feb. 26, 1929.

UNITED STATES "PATENT OFFICE."

CHARLES r. RUBEL, OF CHICAGO, ILLINOIS, ASSIGNOR 'ro UNION SPECIAL mc'nnu: COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION or ILLINOIS.

Application filed April 27, 1925. Serial No. 26,150.

The invention relates to new and useful improvements in a thread lubricating device for sewing machines and more especially to a lubricating device for a multiple needle leather sewing machine.

An object of the invention is to provide a sewing machine with a bracket attached to the needle head with a holder for a lubricant carried thereby and disposed at one side of the front end of said head so that the threads passing through a thread guide on the upper end of the needle bar on their way to the needles will pass through and will be reciprocated in said lubricant. Another object of the invention is to form said receptacle with a slot in the bottom thereof through which the threads pass and with the front wall of the receptacle inclined relative to the rear wall thereof, so as to retain the lubricant in the receptacle. r

These and other objects will in part be obvious and will in part be hereinaftermore fully described. 7

In the 'drawings'which show by way of illustration one embodiment of the invention Figure 1 is a perspective view of a portion of a sewing machine with the invention applied thereto,

Figure 2 is a plan view of the bracket and receptacle for the lubricant removed from the machine.

Figure 3 is a sectional view on the line 3-3 of Figure 2.

The invention is directed broadly to a device for lubricating the threads of a multiple needle leather stitching machine. This lubricating device includes a receptacle for the lubricant mounted on a bracket arm which is adapted to be attached to the head.

of the sewing machine and when so attached said receptacle lies at the side of the headot' the machine so that the threads passing between the thread guide of the upper end of the needle bar and the eyes of the needle will pass through said lubricant. As the needle bar reciprocates the threads will be drawn down through the lubricantand back up through the lubricant and at each reciprocation they will he stepped further along as the threads are consumed in the stitches. It is understood, of course, that the threads pass through the tension devices before passing through the guide at the upper end of the needle bar and, therefore, the lubricant is applied to the threads after they have passed through the tension and just before they are formed into stitches. Consequently, the tensions and the thread eyes do not strip the threads of the lubricant applied thereto.

Referring more in detail to the drawings the invention'is shown as applied to a sewing machine, including an overhanging arm 1 at the forward end of which is a needle head 2 in which the needle bar 3 reciprocates. This needle bar is reciprocated by the usual lever 4 which is connected to the needle bar by a link 5. At the upper end of the needlebarthere is an arm 6 provided with a series of thread eyes 7. The needle threads are indicated at 8 in the drawing. The needles are indicated at 9 and in the present illustrated machine there are three pairs of needles 9. These needles are clamped in the needle clamplO at the lower end of. the needle'bar. A presser foot 11' holds the material on the work support 12 in the usual way. This presser foot is provided with a series of openings 13, one for each pair. of needles. Cooperating with each pair of needles beneath the work support 12 is the usual thread carrying looper, the thread of which looks both loops of the pair of needles with which it cooperates. The lubricating device consists of a receptacle '14 which is mounted on a bracket arm 15. This bracket arm 15 is secured to the lower bearing 16 of the needle head 2 by means of a threaded bolt 17. There is a bearing plate 18 on the inside of the bracket-which enables this bracket 'to be very rigidly secured to the needle head, The receptacle 14 consists of a back plate 19 which is rigidly secured to the bracket and a front plate 20 which is likewise secured to the bracket arm 15. The front plate 20 lies in a plane cutting the plane contained in the back plate at an acute angle. The lower edge of the plate 20 is, however, slightly spaced "from the lower edge of the plate 19 as clearly shown in Figure 3 of the drawing. The back plate 19 is bent at right angles to'form an end plate 21. The upper edges of the plates 19 and 20rare substantiall parallel and the plate 21 extends forwar so as to slightly overlap the plate 20 throughout its entire height. The plate 20 is likewise bent at right angles to form an inner end late 22. The plates 21 and 22 are spaced rom each other so as to form a slot 23 and this slot 28 leads into the slot 24 formed by the space between the lower edges of the plates 19 and 20. The receptacle formed by these platesw extends wholly to the right of the bracket arm 15 as viewed in Figure l and,

therefore, the receptacle lies at the side of the front end of the overhanging arm 1.

The threads Spassing on-the way to the needle eyes pass through this receptacle, that is, they may be placed in the slot 23 and forced back so as to be caused to run easily down to the slot 24. The receptacle thus formed is filled with a lubricant which is a semi-solid or semi-fluid mass such as wax, soft soap or the like. In view of the fact that the front wall is inclined the lubricant will not pass out through the slot except such part thereof as is taken up by the threads. On'a down stroke'of the needle bar the threads will be drawn through the lubricant. On an up stroke of the needle bar they will be raised up through the lubricant, that is, certain portions of the threads reciprocate in the lubricant, and as the tl "eads are consumed by the forming of stitches new portrons will be brought down into the lulDllCiLIlt; The threads are free after they leave the lubricant from any tensions or the like until they pass through the eyes of the needle and, therefore, the'lubricant taken up by the threads will be carried down into the material and will lubricate the leather or other materialwhich is being stitched.

While I have described the invention as particularly adapted for a multiple needle thread machine, it will be understood, of course, that the receptacle for the lubricant may-be equally used on a single thread machine,'and it is understood that the invention' is sufliciently broad to cover either a single needle machine or a multiple needle machine.

- t It obvious that minor changes in the upper end of the needle bar, through which thethread passes on the way to the needle, a bracket secured to the needle head, a re ceptacle carried by said bracket having oiling means therein, said bracket being so disposed on theneedle head that the thread passing between the guide at the upper end of'the needlebar and the eye of the needle passes through said rec ptacle in contact with the oiling means and'is moved back and forth through said receptacle as the needle bar reciprocates, the front wall of said receptacle being supported at one end of the rceotacle only and spaced from the other end thereof whereby to form a slot through which the thread by a lateral movement may be passed and properly positioned for passing through the receptacle.

2. A sewing machine including in combination, a needle head, a reciprocating needle bar mounted therein, a needle carried by said bar, a thread guide carried by the uppeiuend of the needle bar, through which the thread passes on the way to the needle, a bracket secured to the needle head,

a receptacle carried by said bracket having oiling means therein, said bracket being so disposed on the needle head that-the thread hissing between the guide. at the upper end of the needle bar and the eye of the needle passes through said receptacle in contact ith the oiling means and is moved back and forth through said receptacle as the needle bar reciprocates, said receptacle beingv wedge-shaped so that when the oiling means is pressed down into the receptacle, it will be pressed against the needle thread, the front wall of said receptacle being supportd at one end of the receptacle only and spaced from the other end thereof whereby to form a slot through which the thread by a lateral movement may be passed and prop erly positioned for passing through the receptacle.

3. A. sewing machine including in combination a needle head, a reciprocating needle bar mounted thereon, a needle carried by said bar, thread guide carried by the upper. end of the needle bar through which the thread passes on its way to the needle, a

bracket secured to the head of the machine, a receptacle carried by said bracket and lo cated in front of the head of the machine, i* which receptacle a semi-solid lubricant may be placed, said receptacle having its front wall inclined relative to the rear wall but spaced therefrom at the lower edge so as to retain the semi-solid lubricant and permit the threads to pass therethrough as they pass tl'irough the receptacle, one of the end walls of the receptacle being formed by bending the front and rear plates of the reccptacle and spacing thesaine fronii each other so as to provide a slot permitting the thread to be moved laterally into the receptacle and into the opening of the bottom thereof.

In testimony whereof, I affix my signature.

, CHARLES r. miner 

